I recently bought BL unit for my desktop PC. I usually burn DVD's of 100 GB on x4, sometimes even x2. The dvd's I use are from ebay, Verbatim blank dvd's. Now, the problem is not in burning, it's when I want to watch some video that I burned after some time it's burned. For example, when I burn my videos I always check if the videos are playable after burning, and if they do I know everything is ok. My question are: 1) is it normal that I need to wait, like 1-2 min for dvd media to load the files that are on the dvd?(maybe it is, considering the size); 2) is it normal that after I watched certain videos couple of times, to suddenly stop working..like in the middle of the movie it starts freezing or it won't start to play at all? I store my dvd's properly, they are not damaged, BL unit is new, videos that I burned are in working order. Thanks for the help.

I recently bought BL unit for my desktop PC. I usually burn DVD's of 100 GB on x4, sometimes even x2. The dvd's I use are from ebay, Verbatim blank dvd's.

There is no DVD media made with 100GB capacity. There is such a thing as Verbatim BD-R XL 100GB with a maximum 4x write speed. Burning recordable media at half the maximum speed or close to it is recommended. Burning at 2x should produce better results than 4x or 1x, if the media and drive support 2x. However, if BD-R 25GB or BD-R DL 50GB discs are an option they may be more reliable than BD-R XL. Achieving a good burn for all three layers on a BD-R XL disc is probably not easy.

I have also a question: I read always to burn at lower speed, but what exactly is better then?
My personal opinion now is that the BD / DVD / CD is, when burned at full speed and then verified ok, what would be better if burned at half speed?
Probably to be sure that burning doen‘t fail? But the only thing I can imagine what could happen is the buffer isn‘t filled as fast as the disc is burned, but that scenario is very very old.